know about rosecut diamond

The rose cut was one of the early or antique diamond shapes. It was so named because it resembled a rose bud just before it had opened - with the facets resembling the tightly-packed rose bud petals.

The rose cut diamond has no table (flat top) but a somewhat domed top (somewhere between a pyramid and a hemisphere) consisting of many facets, typically triangular, which meet at a point in the center. It has a completely flat base - in other words, no pavilion (lower area) at all. The Rose Cut Diamond's facets are often in two rows - with "star facets" (often six triangles) in the center and a proportional number of facets in the second row. However, some of the bigger diamonds of old times featured rose cuts with more than two rows of facets.

The rose cut diamond was believed to have been introduced in European cities in 1520, although some say the rose cut originated in India in around 1400. However despite having been the cut of choice between the 16th and 18th centuries the rose cut had fallen from fashion among modern gem cutters by the 20th century. One of the reasons for this is that in old times, diamonds were cut more to maximize carat weight - whereas nowadays, with the evolution of technology designed to bring out the full sparkle of the gems, "brilliance" and "fire" are more prized; and more of the original rough diamond tends to be removed in the process. Old rose cut diamonds have less fire than their more modern, brilliant cut counterparts - and hence they fell from popularity when new, advanced cutting techniques were devised. [2]

In ancient jewelry settings, rose cut diamonds were sometimes backed by a thin layer of shiny metal foil in order to reflect light back up to the crown (upper surface). [2]

Most of the old rose cut diamonds were refaceted into brilliants using modern technology - which means that true antique rose cut diamonds have become scarce and valuable. In general, antique diamonds are valued differently to modern diamonds, and comparing the two types may be misleading.[3]